# Rational Numbers class 8 Notes Mathematics

## myCBSEguide App

CBSE, NCERT, JEE Main, NEET-UG, NDA, Exam Papers, Question Bank, NCERT Solutions, Exemplars, Revision Notes, Free Videos, MCQ Tests & more.

Rational Numbers class 8 Notes Mathematics in PDF are available for free download in myCBSEguide mobile app. The best app for CBSE students now provides Rational Numbers class 8 Notes Mathematics latest chapter wise notes for quick preparation of CBSE exams and school-based annual examinations. Class 8 Mathematics notes on Chapter 1 Rational Numbers class 8 Notes Mathematics are also available for download in CBSE Guide website.

## Rational Numbers class 8 Notes Mathematics

Download CBSE class 8th revision notes for Chapter 1 Rational Numbers class 8 Notes Mathematics in PDF format for free. Download revision notes for  Rational Numbers class 8 Notes Mathematics and score high in exams. These are the Rational Numbers class 8 Notes Mathematics prepared by team of expert teachers. The revision notes help you revise the whole chapter in minutes. Revising notes in exam days is on of the best tips recommended by teachers during exam days.

## CBSE Class 8 Revision Notes Maths Rational Numbers

• Rational numbers are closed under the operations of addition, subtraction and multiplication.
• The operations addition and multiplication are
(i) commutative for rational numbers.
(ii) associative for rational numbers.
• The rational number 0 is the additive identity for rational numbers.
• The rational number 1 is the multiplicative identity for rational numbers.
• The additive inverse of the rational number ${{a} \over b}$ is ${{a} \over b}$ and vice-versa.
• The reciprocal or multiplicative inverse of the rational number ${{a} \over b}$ is ${{c} \over d}$ if ${{a} \over b}$x${{c} \over d}$=1
• Distributivity   of rational numbers: For all rational numbers a, b and c,
a(b + c) = ab + ac    and  a(b – c) = ab – ac
• Rational numbers can be represented on a number line.
• Between any two given rational numbers there are countless rational numbers. The idea of mean helps us to find rational numbers between two rational numbers.
• Positive Rationals: Numerator and Denominator both are either positive or negative. Example: ${{4} \over 7}, {{-3} \over -4}$
• Negative Rationals: Numerator and Denominator both are of opposite signs. Example: ${{-2} \over 11}, {{4} \over -9}$
• Additive Inverse: Additive inverse (negative) ${{a} \over b}$+${{-a} \over b}$=${{-a} \over b}$+${{a} \over b}$=0, ${{-a} \over b}$ is the additive inverse of ${{a} \over b} \;and\; {{a} \over b}$ is the additive inverse of ${{-a} \over b}$.
• Multiplicative Inverse (reciprocal): ${{a} \over b}$x${{c} \over d}$=1=${{c} \over d}$x${{a} \over b}$ where ${{c} \over d}$ is the reciprocal of ${{a} \over b}$. Zero has no reciprocal. The reciprocal of 1 is1 and of -1 is -1.

## CBSE Class 8 Revision Notes and Key Points

Rational Numbers class 8 Notes Mathematics. CBSE quick revision note for class-8 Mathematics, Physics, Chemistry, Biology and other subject are very helpful to revise the whole syllabus during exam days. The revision notes covers all important formulas and concepts given in the chapter. Even if you wish to have an overview of a chapter, quick revision notes are here to do it for you. These notes will certainly save your time during stressful exam days.

To download Rational Numbers class 8 Notes Mathematics, sample paper for class 8 Chemistry, Physics, Biology, History, Political Science, Economics, Geography, Computer Science, Home Science, Accountancy, Business Studies and Home Science; do check myCBSEguide app or website. myCBSEguide provides sample papers with solution, test papers for chapter-wise practice, NCERT solutions, NCERT Exemplar solutions, quick revision notes for ready reference, CBSE guess papers and CBSE important question papers. Sample Paper all are made available through the best app for CBSE students and myCBSEguide website.